v4.19.13 snapshot.
diff --git a/security/apparmor/policy_ns.c b/security/apparmor/policy_ns.c
new file mode 100644
index 0000000..1a7cec5
--- /dev/null
+++ b/security/apparmor/policy_ns.c
@@ -0,0 +1,414 @@
+/*
+ * AppArmor security module
+ *
+ * This file contains AppArmor policy manipulation functions
+ *
+ * Copyright (C) 1998-2008 Novell/SUSE
+ * Copyright 2009-2017 Canonical Ltd.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, version 2 of the
+ * License.
+ *
+ * AppArmor policy namespaces, allow for different sets of policies
+ * to be loaded for tasks within the namespace.
+ */
+
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+
+#include "include/apparmor.h"
+#include "include/cred.h"
+#include "include/policy_ns.h"
+#include "include/label.h"
+#include "include/policy.h"
+
+/* root profile namespace */
+struct aa_ns *root_ns;
+const char *aa_hidden_ns_name = "---";
+
+/**
+ * aa_ns_visible - test if @view is visible from @curr
+ * @curr: namespace to treat as the parent (NOT NULL)
+ * @view: namespace to test if visible from @curr (NOT NULL)
+ * @subns: whether view of a subns is allowed
+ *
+ * Returns: true if @view is visible from @curr else false
+ */
+bool aa_ns_visible(struct aa_ns *curr, struct aa_ns *view, bool subns)
+{
+ if (curr == view)
+ return true;
+
+ if (!subns)
+ return false;
+
+ for ( ; view; view = view->parent) {
+ if (view->parent == curr)
+ return true;
+ }
+
+ return false;
+}
+
+/**
+ * aa_na_name - Find the ns name to display for @view from @curr
+ * @curr - current namespace (NOT NULL)
+ * @view - namespace attempting to view (NOT NULL)
+ * @subns - are subns visible
+ *
+ * Returns: name of @view visible from @curr
+ */
+const char *aa_ns_name(struct aa_ns *curr, struct aa_ns *view, bool subns)
+{
+ /* if view == curr then the namespace name isn't displayed */
+ if (curr == view)
+ return "";
+
+ if (aa_ns_visible(curr, view, subns)) {
+ /* at this point if a ns is visible it is in a view ns
+ * thus the curr ns.hname is a prefix of its name.
+ * Only output the virtualized portion of the name
+ * Add + 2 to skip over // separating curr hname prefix
+ * from the visible tail of the views hname
+ */
+ return view->base.hname + strlen(curr->base.hname) + 2;
+ }
+
+ return aa_hidden_ns_name;
+}
+
+/**
+ * alloc_ns - allocate, initialize and return a new namespace
+ * @prefix: parent namespace name (MAYBE NULL)
+ * @name: a preallocated name (NOT NULL)
+ *
+ * Returns: refcounted namespace or NULL on failure.
+ */
+static struct aa_ns *alloc_ns(const char *prefix, const char *name)
+{
+ struct aa_ns *ns;
+
+ ns = kzalloc(sizeof(*ns), GFP_KERNEL);
+ AA_DEBUG("%s(%p)\n", __func__, ns);
+ if (!ns)
+ return NULL;
+ if (!aa_policy_init(&ns->base, prefix, name, GFP_KERNEL))
+ goto fail_ns;
+
+ INIT_LIST_HEAD(&ns->sub_ns);
+ INIT_LIST_HEAD(&ns->rawdata_list);
+ mutex_init(&ns->lock);
+ init_waitqueue_head(&ns->wait);
+
+ /* released by aa_free_ns() */
+ ns->unconfined = aa_alloc_profile("unconfined", NULL, GFP_KERNEL);
+ if (!ns->unconfined)
+ goto fail_unconfined;
+
+ ns->unconfined->label.flags |= FLAG_IX_ON_NAME_ERROR |
+ FLAG_IMMUTIBLE | FLAG_NS_COUNT | FLAG_UNCONFINED;
+ ns->unconfined->mode = APPARMOR_UNCONFINED;
+ ns->unconfined->file.dfa = aa_get_dfa(nulldfa);
+ ns->unconfined->policy.dfa = aa_get_dfa(nulldfa);
+
+ /* ns and ns->unconfined share ns->unconfined refcount */
+ ns->unconfined->ns = ns;
+
+ atomic_set(&ns->uniq_null, 0);
+
+ aa_labelset_init(&ns->labels);
+
+ return ns;
+
+fail_unconfined:
+ kzfree(ns->base.hname);
+fail_ns:
+ kzfree(ns);
+ return NULL;
+}
+
+/**
+ * aa_free_ns - free a profile namespace
+ * @ns: the namespace to free (MAYBE NULL)
+ *
+ * Requires: All references to the namespace must have been put, if the
+ * namespace was referenced by a profile confining a task,
+ */
+void aa_free_ns(struct aa_ns *ns)
+{
+ if (!ns)
+ return;
+
+ aa_policy_destroy(&ns->base);
+ aa_labelset_destroy(&ns->labels);
+ aa_put_ns(ns->parent);
+
+ ns->unconfined->ns = NULL;
+ aa_free_profile(ns->unconfined);
+ kzfree(ns);
+}
+
+/**
+ * aa_findn_ns - look up a profile namespace on the namespace list
+ * @root: namespace to search in (NOT NULL)
+ * @name: name of namespace to find (NOT NULL)
+ * @n: length of @name
+ *
+ * Returns: a refcounted namespace on the list, or NULL if no namespace
+ * called @name exists.
+ *
+ * refcount released by caller
+ */
+struct aa_ns *aa_findn_ns(struct aa_ns *root, const char *name, size_t n)
+{
+ struct aa_ns *ns = NULL;
+
+ rcu_read_lock();
+ ns = aa_get_ns(__aa_findn_ns(&root->sub_ns, name, n));
+ rcu_read_unlock();
+
+ return ns;
+}
+
+/**
+ * aa_find_ns - look up a profile namespace on the namespace list
+ * @root: namespace to search in (NOT NULL)
+ * @name: name of namespace to find (NOT NULL)
+ *
+ * Returns: a refcounted namespace on the list, or NULL if no namespace
+ * called @name exists.
+ *
+ * refcount released by caller
+ */
+struct aa_ns *aa_find_ns(struct aa_ns *root, const char *name)
+{
+ return aa_findn_ns(root, name, strlen(name));
+}
+
+/**
+ * __aa_lookupn_ns - lookup the namespace matching @hname
+ * @base: base list to start looking up profile name from (NOT NULL)
+ * @hname: hierarchical ns name (NOT NULL)
+ * @n: length of @hname
+ *
+ * Requires: rcu_read_lock be held
+ *
+ * Returns: unrefcounted ns pointer or NULL if not found
+ *
+ * Do a relative name lookup, recursing through profile tree.
+ */
+struct aa_ns *__aa_lookupn_ns(struct aa_ns *view, const char *hname, size_t n)
+{
+ struct aa_ns *ns = view;
+ const char *split;
+
+ for (split = strnstr(hname, "//", n); split;
+ split = strnstr(hname, "//", n)) {
+ ns = __aa_findn_ns(&ns->sub_ns, hname, split - hname);
+ if (!ns)
+ return NULL;
+
+ n -= split + 2 - hname;
+ hname = split + 2;
+ }
+
+ if (n)
+ return __aa_findn_ns(&ns->sub_ns, hname, n);
+ return NULL;
+}
+
+/**
+ * aa_lookupn_ns - look up a policy namespace relative to @view
+ * @view: namespace to search in (NOT NULL)
+ * @name: name of namespace to find (NOT NULL)
+ * @n: length of @name
+ *
+ * Returns: a refcounted namespace on the list, or NULL if no namespace
+ * called @name exists.
+ *
+ * refcount released by caller
+ */
+struct aa_ns *aa_lookupn_ns(struct aa_ns *view, const char *name, size_t n)
+{
+ struct aa_ns *ns = NULL;
+
+ rcu_read_lock();
+ ns = aa_get_ns(__aa_lookupn_ns(view, name, n));
+ rcu_read_unlock();
+
+ return ns;
+}
+
+static struct aa_ns *__aa_create_ns(struct aa_ns *parent, const char *name,
+ struct dentry *dir)
+{
+ struct aa_ns *ns;
+ int error;
+
+ AA_BUG(!parent);
+ AA_BUG(!name);
+ AA_BUG(!mutex_is_locked(&parent->lock));
+
+ ns = alloc_ns(parent->base.hname, name);
+ if (!ns)
+ return ERR_PTR(-ENOMEM);
+ ns->level = parent->level + 1;
+ mutex_lock_nested(&ns->lock, ns->level);
+ error = __aafs_ns_mkdir(ns, ns_subns_dir(parent), name, dir);
+ if (error) {
+ AA_ERROR("Failed to create interface for ns %s\n",
+ ns->base.name);
+ mutex_unlock(&ns->lock);
+ aa_free_ns(ns);
+ return ERR_PTR(error);
+ }
+ ns->parent = aa_get_ns(parent);
+ list_add_rcu(&ns->base.list, &parent->sub_ns);
+ /* add list ref */
+ aa_get_ns(ns);
+ mutex_unlock(&ns->lock);
+
+ return ns;
+}
+
+/**
+ * aa_create_ns - create an ns, fail if it already exists
+ * @parent: the parent of the namespace being created
+ * @name: the name of the namespace
+ * @dir: if not null the dir to put the ns entries in
+ *
+ * Returns: the a refcounted ns that has been add or an ERR_PTR
+ */
+struct aa_ns *__aa_find_or_create_ns(struct aa_ns *parent, const char *name,
+ struct dentry *dir)
+{
+ struct aa_ns *ns;
+
+ AA_BUG(!mutex_is_locked(&parent->lock));
+
+ /* try and find the specified ns */
+ /* released by caller */
+ ns = aa_get_ns(__aa_find_ns(&parent->sub_ns, name));
+ if (!ns)
+ ns = __aa_create_ns(parent, name, dir);
+ else
+ ns = ERR_PTR(-EEXIST);
+
+ /* return ref */
+ return ns;
+}
+
+/**
+ * aa_prepare_ns - find an existing or create a new namespace of @name
+ * @parent: ns to treat as parent
+ * @name: the namespace to find or add (NOT NULL)
+ *
+ * Returns: refcounted namespace or PTR_ERR if failed to create one
+ */
+struct aa_ns *aa_prepare_ns(struct aa_ns *parent, const char *name)
+{
+ struct aa_ns *ns;
+
+ mutex_lock_nested(&parent->lock, parent->level);
+ /* try and find the specified ns and if it doesn't exist create it */
+ /* released by caller */
+ ns = aa_get_ns(__aa_find_ns(&parent->sub_ns, name));
+ if (!ns)
+ ns = __aa_create_ns(parent, name, NULL);
+ mutex_unlock(&parent->lock);
+
+ /* return ref */
+ return ns;
+}
+
+static void __ns_list_release(struct list_head *head);
+
+/**
+ * destroy_ns - remove everything contained by @ns
+ * @ns: namespace to have it contents removed (NOT NULL)
+ */
+static void destroy_ns(struct aa_ns *ns)
+{
+ if (!ns)
+ return;
+
+ mutex_lock_nested(&ns->lock, ns->level);
+ /* release all profiles in this namespace */
+ __aa_profile_list_release(&ns->base.profiles);
+
+ /* release all sub namespaces */
+ __ns_list_release(&ns->sub_ns);
+
+ if (ns->parent) {
+ unsigned long flags;
+
+ write_lock_irqsave(&ns->labels.lock, flags);
+ __aa_proxy_redirect(ns_unconfined(ns),
+ ns_unconfined(ns->parent));
+ write_unlock_irqrestore(&ns->labels.lock, flags);
+ }
+ __aafs_ns_rmdir(ns);
+ mutex_unlock(&ns->lock);
+}
+
+/**
+ * __aa_remove_ns - remove a namespace and all its children
+ * @ns: namespace to be removed (NOT NULL)
+ *
+ * Requires: ns->parent->lock be held and ns removed from parent.
+ */
+void __aa_remove_ns(struct aa_ns *ns)
+{
+ /* remove ns from namespace list */
+ list_del_rcu(&ns->base.list);
+ destroy_ns(ns);
+ aa_put_ns(ns);
+}
+
+/**
+ * __ns_list_release - remove all profile namespaces on the list put refs
+ * @head: list of profile namespaces (NOT NULL)
+ *
+ * Requires: namespace lock be held
+ */
+static void __ns_list_release(struct list_head *head)
+{
+ struct aa_ns *ns, *tmp;
+
+ list_for_each_entry_safe(ns, tmp, head, base.list)
+ __aa_remove_ns(ns);
+
+}
+
+/**
+ * aa_alloc_root_ns - allocate the root profile namespace
+ *
+ * Returns: %0 on success else error
+ *
+ */
+int __init aa_alloc_root_ns(void)
+{
+ /* released by aa_free_root_ns - used as list ref*/
+ root_ns = alloc_ns(NULL, "root");
+ if (!root_ns)
+ return -ENOMEM;
+
+ return 0;
+}
+
+ /**
+ * aa_free_root_ns - free the root profile namespace
+ */
+void __init aa_free_root_ns(void)
+{
+ struct aa_ns *ns = root_ns;
+
+ root_ns = NULL;
+
+ destroy_ns(ns);
+ aa_put_ns(ns);
+}